1. Field of the Invention
The present invention relates to a screwdriver shank having a universal joint with a screwdriver handle to allow tightening/loosening of a fastener that cannot be driven at an upright position of the screwdriver.
2. Description of the Related Art
Screwdrivers are useful in daily life. However, it is troublesome, sometimes impossible, to use screwdrivers when the fasteners to be tightened/loosened cannot be driven at an upright position of the screwdrivers. The present invention is intended to provide a screwdriver shank having a universal joint with a screwdriver handle to solve this problem.
A screwdriver in accordance with the present invention comprises a handle including a seat, a shank having a first end in universal joint with the seat and a second end engaged with a tool bit, and means for retaining the first end of the shank and the seat together such that the first end of the shank and the seat rotate together when the handle is turned.
The first end of the shank is in the form of a ball. The retaining means is an elastic element mounted in the seat. The seat includes a pinhole, the ball of the shank includes a pinhole, and a pin is extended through the pinhole of the seat and the pinhole of the shank. The elastic element biases the ball to press against the pin. An outer periphery of the ball presses against an inner periphery of the seat. The pinhole of the ball is longer than the pinhole of the seat. A sleeve is mounted around the shank and slidable along a longitudinal direction of the shank, the sleeve carrying a plurality of tool bits. The sleeve includes a tubular portion that houses the pin and a portion of the seat. The tubular portion of the sleeve includes a plurality of ribs for frictional contact with an outer periphery of the seat.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.